Governing device for gas-engines



No. 62I,III. Patented Mar. '14, I899.

a. w. LEWIS.

GOVERNING DEVICE FOR GAS ENGINES.

(Application filed Jim 21, 1594. Renewal! se t. 14, 1895.)

(No Model.)

2 Sheets-Sheet l.

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I jaw/72252" 2 W QM wa ww f 5 No. 62l,l|l. 'Patented Mar. l4, I899- G.W. LEWIS. GOVERNING DEVICE FOR GAS ENGINES.

(Application filed June 21, 1894. Renewed Sept. 14, 1898.)

' 2 Sheets-Sheet 2.

(No Model.)

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UNITED STATES PATENT Onricn.

GEORGE IV. LEWIS, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE J. THOMPSON &SONS MANUFACTURING COMPANY, OF BELOIT, WISCONSIN.

GOVERNING DEVICE FOR GAS-ENGINES.

SPECIFICATION forming part of Letters Patent No. 621,111, dated March14, 1899.

Application filed June 21, 1894.. Renewed September 14, 1898. Serial No.690,985. (No model.)

T0 at whom it may concern:

Be it known that I, GEORGE W. Lnwrs, of Chicago, in the county ofCook-and State of Illinois, have invented certain new and usefulImprovements in Governing Devices for Engines; and I do hereby declarethat the following is a full, clear, and exact description thereof,reference being had to the accompanying drawings, and to the letters ofreference marked thereon, which form a part of this specification.

This invention relates to speed-governing devices for engines,-adaptedmore especially for explosive gas or vapor engines, but some parts ofwhich are adapted for use in connection with other engines.

The invention consists in the matters hereinafter described, and pointedout in the appended clailns. Certain features of the present inventionconstitute improvements on an engine of the general character set forthin a prior application, Serial No. 482,343, filed by me August 4:, 1893,embracing a construction by which an explosion is made at each alternatestroke of the piston.

The invention may be better understood by reference to the accompanyingdrawings, in which Figure 1 is a view in rear elevation of a gasenginecontaining the improvements constituting myinvention. Fig. 2 is a plansection of the parts more directly concerned in governing the engine,taken on line 2 2 of Fig. 1. Fig. 3 is a detail section taken on line 33 of Fig. 2. Figs. 4 and 5 are detail views of a wedge which forms partof the governing deprovided with two chests B B arranged on oppositesides of the closed end of said cylinder,the first-namedchest,B,containing a sup ply-valve, of which the valve-stem B only isshown, and the last-named chest, B containment of the valve-stems B andB crank-shaft.

ing the exhaust-valve, which is attached to the stem 13. v

B is a supply-pipe for gas or vapor and air, leading to the chest B froma suitable mixing-chamber or other source of supply, and B is anexhaust-pipe leading from the chest B to any suitable point ofdischarge. The valves within the said valve-chests are constructed andoperate in the same manner as those described in said prior applicationfor patent, both of said valves being inwardlyopening valves operated byendwise move- The inlet-valve is opened automatically to admit theadmixture of air and gas to the cylinder by the suction of the piston inits forward or outward movement in the cylinder, it being of courseunderstood that in this type of engine the explosion takes place atevery other forward stroke of the engine and that the charge of air andgas is drawn into the cylinder in the forward strokes of the pistonpreceding each explosion, as fully set forth in said prior application.

For the control of the exhaust-valve of the engine in the regularoperation thereof devices are provided as follows: G is a shaft mountedin suitable bearings at the side of the machine and provided with aworm-wheel g, which is engaged by a worm g on the The said shaft Gcarries a cam H, which is adapted to act upon one end of acentrally-pivoted lever I, which bears upwardly at its opposite endagainstthe shoulder 29 on the downwardly-directed valve-stem B of theexhaust-valve. A spring J, attached to the valve-stem and to themachine-frame, serves to draw the valve toward its seat. Said spring isprovided with suitable devices by which its tension may be adjusted. Thesame is herein shown as consisting of an adjusting-bolt j, which passesthrough a log ct on the frame and is provided below said lug with a nutj, which may be turned on the bolt to draw it downwardly or permit it torise for the purpose of varying the tension or strength of the spring J.

The speed-governing mechanism herein shown embraces acentrifugally-actin g speedgovernor, which is constructed as follows: K

is an arm or rod which is constructed to oscillate about a suitablecenter of rotation, said rod being herein shown as secured in a sleeveis, which engages a stationary pin or stud I, attached to a bracket L onthe machine-frame. The said pin L is shown as arranged horizontally, andthe arm K, thus mounted,swings in a vertical plane; but this feature ofconstruction is not essential. Oscillatory move ment is given to the armK by means of an eccentric M on the shaft G, which eccentric isconnected with the crank-arm on the sleeve 7t by means of aneccentric-rod M. N is a weight arranged to move freely on the arm K andwhich is connected, by means of a rod 0, with a horizontally-arrangedsliding wedge P, which is adapted for contact with a shoulder orprojection b on the stem 13 of the inlet-valve. In the particularconstruction illustrated the wedge P is mounted to slide in the bracketL by means of lateral flanges 17 on the wedge, adapted to engageguide-grooves Z in the bracket, and said wedge is slotted longitudinallyand so arranged that the stem B which passes through and is guided inthe bracket L, passes also through the slot in the wedge. The shoulder bof the valvestem is shown as being formed by means of nuts engaging thescrew-threaded end portion of the stem, this construction enabling theposition of the shoulder to be adjusted as desired. The nuts, arrangedas described, strike the lower or inclined surface of the wedge when thevalve is lifted to admit the admixture of air and gas in the forwardstroke of the piston, thereby limiting the upward movement of the valveaccording to the position occupied by the wedge. The arm K beingarranged so as to oscillate in either direction from a horizontalposition and the wedge being arranged to slide horizontally, theconnecting-rod will obviously serve to transmit motion continuously fromthe weight to the wedge, so that the latter will be moved forwardly orbackwardly as the weight moves outwardly or inwardly on the said arm.The outward movement of the weight on the arm is produced by centrifugalaction arising from the oscillatory movement of the arm, and in order todraw the weight inwardly on the arm a spring K is applied in a mannersuitable for the purpose, said spring being shown as of coiled form andconnected with the arm and the weight. As a convenient construction saidspring is herein shown as coiled around the arm for a part of its lengthand as being attached at its outer end to the weight N and at its innerend to a collar k which is adjustably secured to the arm in order toenable the tension of the spring to be adjusted as desired. Stops orshoulders at n on the rod K serve to lim it the inward and outwardmovement of the said weight N. While said weight may be made to slide onthe arm or rod K and may have antifriction-rollers or other antifrictiondevices to insure its moving freely on the rod, yet, as a furtherimprovement, I

' propose to make the aperture in the weight through which the armpasses larger than the arm in the direction of the plane of oscillationof the arm and preferably slightly larger also in a plane at rightangles to the plane of oscillation. By making said aperture wider thanthe arm in the direction of the oscillation of the arm the weight moveson the arm with an intermittent or step-by-step movement, this arisingfrom the fact that the weight is caused to move sidewise relatively tothe arm at each stroke of the latter, the arm being brought againstfirst one side then the other side of the aperture as the arm reachesthe extreme limit of its throw in either direction. When the aperture inthe weight is thus made larger than the arm, the advance or shiftingmovement of the weight on the arm takes place during the time when theweight is free from contact with the arm, or, in other words, during theperiod between the time the arm leaves contact with one side of theaperture and comes in contact with the opposite side thereof. The weightwhen thus made is of course free from frictional contact with the armduring the period of such motion relatively to the arm, and outward orinward movement of the weight on the arm takes place at such time,because there is then little or no frictional engagement between theweight and the arm. In practice the weight, when made as described, isfound to move on the arm not uniformly or continuously, but with astep-by-step movement, as above described, the same being shiftedsteadily and gradually inward and outward, according to the speed atwhich the arm is oscillated, an increase in speed suliicient to make thecentrifugal action of the weight overcome the spring resulting in theweight moving outwardly on the arm and a decrease in speed having thereverse effect.

In order to avoid noise or jar, which would otherwise be produced to agreater or less extent by the lateral movement of the weight on the arm,I propose to provide the opening or aperture n of the weightN with alining a of leather or the like, as clearly seen in Fig. 7.

In operation of the governing devices thus constructed oscillatorymovement will be given to the arm K through the medium of the shaft Gand eccentric M continuously during the operation of the engine. 13ysuch oscillatory movement of the shaft the weight N will be movedinwardly oroutwardly thereon in the manner hereinbefore described and byits movement will shift the wedge P inwardly or outwardly. hen the wedgeis shifted to bring its thicker part opposite the valve-stem B, thevalve attached thereto will be lifted only slightly, and under thesuction produced by the forward movement of the piston the admixture ofair and gas in small quantity only will enter the cylinder from thesupplypipe B When, on the contrary, the weight is moved inwardly upon adecrease in speed of the engine, the thin part of the wedge will comeopposite the valve-stem and the valve will be afforded a greater degreeof movement, thereby admitting a greater quantity of the admixture ofairand gas and giving greater power to the engine.

I propose, in connection with a speed-governor of the kind shown or anyother form of speed-governor which variably controls or limits theextent of opening of the inlet-valve, to make the spring J, which holdsthe exhaustvalve closed, of such strength or to place it under suchtension that said exhaust-valve will open automatically in the outstrokeof the piston, so as to admit air to the cylinder at the same time thatair and gas is admitted through the inlet-valve. Said spring for thispurpose is made to act on the exhaust-valve with a pressure less thanthat coming on the said exhaust-valve by reason of the suction of thepiston in its advance movement. By so constructing the spring J that itwill allow the exhaust-valve to open automatically durin g the forwardstroke of the piston I provide means for supplying air to the cylinder,in addition to the admixture of air and gas drawn into the cylinderthrough the inlet-valve, sufficient tofill the cylinder, it beingobvious that in the operation of the device when thus made if theinlet-valve be opened to a small extent onlya large quantity of air willbe drawn inwardly through the exhaust-valve, but if the inlet-valve beopened nearly or quite to its fullest extent little or no air will bedrawn in through the exhaust-valve. By reason of the improved actionresulting from the making of the spring of such strength as to permitthe exhaust-valve to open during the time that the inlet-valve is partlyclosed this construction is of great importance and is claimed herein aspart'of my invention. The adjusting device for changing the tension ofthe said spring is also of importance, because it enables the spring tobe easily adjusted in strength to open as soon as the necessary externalpressure is brought thereon.

In Fig. 6. I have shown a governing device embodying the same generalprinciples of con struction present in the device illustrated in thefigures before referred to, but diifering therefrom in its details. Inthis instance the arm or rod K, which carries the governingweight N, ismounted on a pivot q, attached to a bracket Q in such manner that saidarm swings at either side of a vertical line when oscillated. The weightin this instance tends to move outwardly by gravity, as well as bycentrifugal force, and a spring R, which is applied to retract theweight, is made ofsuch strength as to overcome the. gravity of the samewhen the arm is not in motion. Oscillatory movement is given to the armK in this instance by means of a double cam S on the shaft G, againstwhich a rigid arm K attached to the arm K, is held by means of acontractile spring T. A bell-crank lever U is pivoted to the bracket Q,and one of its arms depends from said bracket and is attached to thesliding wedge P. The other arm to of said lever is connected with theweight N by means of a connecting-rod U. The spring R is in thisinstance shown as a coiled spring of contractile form and as connectedwith the arm to of the bell-crank lever U and a stationary part of themachine-frame. An adjusting device for said spring is herein shown, thesame consisting of a screw-bolt R, which passes through a bracket 1 onthe engine-frame and on which is placed a nut r, which bears against thebracket and which may be turned on the bolt to increase or decrease thetension of the spring.

I claim as my invention 1. The combination with a valve, of aspeedgovernor .comprising an oscillating arm, a weight applied to movefreely on the arm, meansacting yieldingly on the weight and tending todraw it inwardly on the arm and connecting mechanism between the weightand the valve, whereby the action of the valve will be controlled by themovement of the weight on the arm, substantially as described.

2. The combination with avalve, of aspeedgovernor comprising anoscillating arm, a Weight applied to move freely on the arm, meansacting yieldingly on the weight and tending to draw it inwardly on thearm and connecting mechanism between the weight and the valve, saidweight having an opening for the passage of the armwhich opening islarger than the arm, substantially as described.

3. The combination with an oscillating arm, of a governor-weight appliedto move on the arm, said weight having an aperture for the arm, whichaperture is larger than the arm and is provided with a lining of leatheror the like, substantially as described.

4. The combination with an inlet-valve for the explosive mixture, of aspeed-governor comprising an oscillating arm, a governorweight mountedto move freely endwise of the arm, means acting yieldingly on the weighttending to move it inwardly on the arm and connecting mechanism betweensaid weight and the valve, whereby the opening of the same will bevariably limited, substantially as described.

5. The combination with an inlet-valve for the explosive mixture, of aspeed-governor comprising an oscillating arm, a governorweight mountedto .move freely endwise of the arm, a spring applied to the weight andtending to draw the same inwardly on the arm, and connecting mechanismbetween said weight and the valve, whereby the opening of the same willbe variably limited, substantially as described.

6. A speed-governor comprising an oscillating arm, a weight mounted tomove freely endwise of the arm, and a sliding wedge connected with theweight and receiving motion from the latter, substantially as described.

7. The combination with an inlet-valve for the explosive mixture, of aspeed-governor vIOO ment of the inlet-valve, a connecting mechanismbetween said weight and the wedge by which the latter is actuated, and aspring applied to draw the weight inwardly on the arm, substantially asdescribed.

In testimony that I claim the foregoing as my invention I affix mysignature in pres- 20 ence of two witnesses.

GEORGE \V. LEWIS.

WV itnesses:

0. CLARENCE PooLE, WM. L. HALL.

